Abstract: The complement component factor B (Bf) polymorphism of Yao, Han, Zhuang, Miao and Uigur in China was investigated by means of high voltage agarose gel electrophoresis and sebsequent immunofixation. The results showed that the Bf*S gene frequencies were the highest in all five ethnic groups. These were Yao 0.9071, Han 0.8727, Zhuang 0.8426, Miao 0.7667, and Uigur 0.6622, respectively. The Bf*F was the second major gene in these ethnic groups: Uigur 0.2680, Miao 0.2000, Zhuang 0.1343, Han 0.1159 and Yao 0.0929, respectively. The BfSO7 was the less common gene: Uigur 0.0586, Miao 0.0333, Zhuang 0.0231, Han 0.0091, and Yao 0.0000, respectively. In addition, some rare phenotypes were found, such as SO 45 in Han and FO 65 and F1 in Uigur.

Key words: Properdin factor B; Genetic polymorphism; Human genetics